Paper folders are used to fold a sheet of paper into sections in order to fit this sheet into an envelope. Typically, the paper folders use a series of rollers to grab and move the sheet of paper being folded through the folding process, and crease the material as it passes between sets of contacting rollers.
Contemporary paper folders could fold the sheet of paper into two sections in one fold, or into three or four sections in two folds. The four section fold is usually limited to the double parallel fold. The most common folds are: half-fold, letter fold, z-fold, double parallel fold, and brochure fold.
The variety of paper available on the market today causes difficulty with the automatic feed. Some paper is thin, other is thick. The automatic paper folder must be adaptable to virtually any paper available on the market.
Another important requirement for today's paper folder is the choice of automatic or manual feed. The user can feed the paper either sequentially sheet-by-sheet, or automatically by placing a stack of paper into a paper feed assembly.
Depositing the stack of paper permits a high-speed operation, while feeding the sheets sequentially is time-consuming. However, the automatic feeding of the stapled sets is not possible.
The U.S. Pat. No. 4,869,712 Masahiro Ishino discloses a paper folding apparatus having two inlets, one adapted for the automatic feeding, and another—for manual feeding. Having two inlets also requires in two paper paths with all the extra parts and increased size.
In a portable and inexpensive folder, it would be desirable to have a single inlet. A bypass is required in order to feed the stapled sets sequentially through the automatic paper feed inlet.